Various prior art publications relate to fee weight devices. For example:                Prior art reveals a weight adjustable dumbbell for performing a push up (US20100022365) Steve Ngu (Jan. 28, 2010);        Prior art reveals a dual purpose dumbbell (US20090156375) Pang-Ching Chiang (Jun. 18, 2009);        Prior art reveals a dumbbell weight training device with detachable weight plates (US20090048079) Mark Nalley (Feb. 19, 2009);        Prior art reveals a dumbbell weight training device with detachable weight plates (U.S. Pat. No. 7,588,520) Mark Nalley (Sep. 15, 2009);        Prior art reveals a fitness dumbbell with an ornamental design of a circle with a handle through the middle. (USD575,361) Charles P. Davis (Aug. 19, 2008) and (USD274,283) Forrest S. Wright (Jun. 12, 1984);        Prior art reveals a fitness dumbbell with an ornamental design of an oblong circle with a handle through the middle. (USD244,628) Forrest S. Wright (Jun. 7, 1977);        Prior art reveals a fitness dumbbell with an ornamental design of a three layered circle with a handle through the middle (USD438,265) Paul J. Fenelon (Feb. 27, 2001);        Prior art reveals a pushup exercise device that allows the user to perform pushups with the wrists in a neutral position with a rotating handle however it does not provide any significant external weight that would allow the user to perform more than just pushups with the device (D597,153) Mark B. Friedman (Jul. 28, 2009).        
As is known in the art, a dumbbell is a conventional weight training device that has long been used by body builders and others to improve their physical strength and appearance as part of a weight training or exercise program. Such a dumbbell typically includes a cylindrical gripping handle that carries a pair of weight plates at opposite ends thereof. In this regard, the weight plates are typically fixedly and connected to the ends of the gripping handle. Should the user wish to increase the weight to be lifted, he/she must find an altogether different dumbbell. In such devices, there is no way for the user to selectively adjust or progressively change the weight of a dumbbell to be used during a workout, such that the gross weight of each dumbbell remains the same at all times.
As a consequence of the foregoing, the fitness center or the user (should the person elect to exercise at their home or office) must maintain many different dumbbells having characteristically different gross weights. Accordingly, the cost to acquire a variety of dumbbells and the space consumed as a result thereof are undesirably increased. Moreover, the user's ability to easily and quickly expand his/her personal weight training program is hampered by the requirement to have ready access to such different dumbbells.
Nevertheless, a number of commercially available adjustable weight dumbbell system are available, such as shown in U.S. Pat. No. 5,839,997 and others. These dumbbell systems are typically mechanically complicated and potentially unstable as they rely on locking mechanisms that can become faulty with progressive use. Therefore, users may experience either confusion which may lead to mistakes when attempting to vary the gross weight of the dumbbell during a workout, or training accidents which can be potentially dangerous.
Likewise a commercially available rotating pushup device is available (e.g., U.S. Pat. No. 7,468,025) that allows the user to perform a pushup exercise while freely rotating the wrists through supination and pronation which allows for increased chest, shoulder, forearm and triceps muscle recruitment without compromising wrist joint integrity. This system however is significantly limited in its strength building applications beyond just this one exercise as it does not allow the user to utilize the device for any other form of overloaded exercise. The muscle overload that is lacking from this device prevents it from being used for any other strength building purpose (as a traditional dumbbell would) than the push up exercise that it is used for. The limitation to the user to just performing pushups with this device will compromise their potential total body strength gains by not allowing them to use the device to train their legs, back, abs, and the aforementioned muscles (chest, shoulders, forearms, triceps) in more direct, diverse and multiple ways.